Electric bed frame

ABSTRACT

An electric bed frame, including a frame body, an electric support plate, a driving device, and bed legs detachably connected to the frame body. The frame body includes a first base frame and a second base frame, the electric support plate includes a first electric support plate connected to the first base frame, and a second electric support plate connected to the second base frame, the first base frame and the first electric support plate form a first folding unit, and the second base frame and the second electric support plate form a second folding unit; the first folding unit and the second folding unit are rotatably connected by a rotation mechanism, and when being rotated to an extreme position, the first folding unit and the second folding unit are parallel, and the driving device is positioned between the first folding unit and the second folding unit.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is based on and claims the priority benefits of China application No. 202121054734.X, filed on May 17, 2021. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.

BACKGROUND Technical Field

The present application relates to the field of an electric bed frame, and more particularly to electric folding bed frames.

Description of Related Art

During logistics transportation, the larger the cargo, the higher the freight. Especially in developed countries with higher labor cost, the freight does not rise uniformly with the sizes of the cargo, but increases in a stepwise manner. Once the size of the cargo is higher than a certain threshold value, the freight is greatly increased even if the size exceeds a little. If the cargo is too large, the cargo is even rejected, logistics distribution cannot be performed.

The bed frame is undoubtedly large-sized cargo, and the common bed frame can be directly detached into rod members and plate members for transportation, and assembled by a buyer after being received. However, the electric bed frame is much more complex than a common bed frame in structure and has the function of adjusting the angles of a plurality of bed plates. If the electric bed frame is also disassembled for transportation, since there are too many electrical components and mechanical structures on the electric bed frame, on the one hand, the assembly difficulty of the buyer is large, and on the other hand, it is difficult to guarantee the use stability after assembly. Therefore, it is difficult to transport by using a disassembly transportation method.

Regarding the related art described above, the inventors believe that there exist defects that the electric bed frame is excessively large and the transportation cost is excessively high.

SUMMARY

In order to reduce the volume occupied by the electric bed frame during transportation, the present application provides an electric bed frame.

The electric bed frame provided in the present application adopts the following technical solutions: an electric bed frame, including a frame body, an electric support plate rotatably connected to the frame body, a driving device connected to the frame body and driving the electric support plate to rotate, and bed legs detachably connected to the frame body, the frame body includes a first base frame and a second base frame, the electric support plate includes a first electric support plate connected to the first base frame, and a second electric support plate connected to the second base frame, the first base frame and the first electric support plate form a first folding unit, and the second base frame and the second electric support plate form a second folding unit; the first folding unit and the second folding unit are rotatably connected by a rotation mechanism, and when the first folding unit and the second folding unit are rotated to an extreme position, the first folding unit and the second folding unit are parallel, and the driving device is positioned between the first folding unit and the second folding unit.

The first electric support plate includes a lumbar support plate fixedly connected to the first base frame and a back support plate rotatably connected to one side of the lumbar support plate, the driving device includes a roller abutting against the back support plate, a first support rod having one end rotatably connected to the roller and the other end rotatably connected to the first base frame, and a first driving cylinder connected to the first base frame and driving the first support rod to push the back support plate close to or away from the first base frame.

By adopting the above technical solution, during transportation, firstly, the bed legs are removed, and then the first folding unit and the second folding unit are folded by a rotation mechanism until the first folding unit and the second folding unit are folded in parallel, and at this time, the length occupied by the bed frame is reduced by half, and a logistics box with a smaller length can be selected, thereby reducing the required transportation length; the driving device is received between the first folding unit and the second folding unit, so that the space between the two folding units can be effectively utilized, there is no need to select a logistics box with larger size for the protruding driving device, and the effects of reducing the transportation volume and reducing the transportation cost are finally achieved.

During normal use after transportation, when the angle of the bed board is controlled by the folding bed frame, the first support rod is jacked up by the first driving cylinder, at this time, the first support rod is rotated around the rotation point of the first base frame to raise the height of the roller. Since the roller always abuts against the back support plate, then the back support plate can be lifted as the roller is lifted, and during the lifting process, abrasion generated by friction due to the rolling of the roller is reduced, and therefore noise is reduced.

Meanwhile, in order to achieve the purpose of reducing the volume, the first driving cylinder needs to be designed as small as possible, so the power will be reduced, and after the roller is used, the frictional resistance during the lifting process can be greatly reduced, and even if the power of the first driving cylinder is reduced, the requirements of the use process can still be satisfied, thereby achieving the purpose of simultaneously satisfying the transportation requirements and the use requirements.

In some embodiments, the roller and the first support rod are provided on each side of the back support plate, and the two first support rods are connected by a linkage rod at one end of each first support rods away from the roller; a cylinder block of the first driving cylinder is rotatably connected to the first base frame, and a piston rod of the first driving cylinder is rotatably connected to the linkage rod.

By adopting the above technical solution, the two first support rods are used to stably support the back support plate, so that the lifting process of the back support plate can be more stable, and the stress is more uniform.

The two first support rods are connected together by the linkage rod and are driven simultaneously, one first driving cylinder is eliminated, on the one hand, the cost is saved, and on the other hand, the volume of the whole bed frame is also reduced.

In some embodiments, the piston rod of the first driving cylinder is connected to the linkage rod by an extension rod, one end of the extension rod is fixedly connected to the linkage rod, the other end of the extension rod is inclined towards the back support plate and is rotatably connected to the piston rod to form a rotation connection point a, and a cylinder block of the first driving cylinder is rotatably connected to the first base frame and forms a rotation connection point b; the distance between the rotation connection point a and the back support plate is smaller than the distance between the rotation connection point b and the back support plate.

Because the length of the first driving cylinder itself is very long, in terms of transportation requirements, in consideration of the reduction of the vertical size during transportation, the more parallel the first driving cylinder and the back support plate is, the smaller the influence of the vertical size during transportation is. Due to the limitation caused by the length of the first driving cylinder, the more the inclination angle between the first driving cylinder and the back support plate tends to be vertical, the larger the occupied space is, the greater the vertical size during transportation is, and the higher the transportation cost is, and therefore, from the perspective of transportation, the first driving cylinder and the back support plate are expected to be more parallel.

However, in terms of the use requirements of users after transportation, in consideration of the lifting of the back support plate, in the case where the inclination angle of the first driving cylinder and the back support plate tends to be more vertical, the smaller the force arm is in lifting, and the more stable the back support plate can be lifted.

Therefore, in order to simultaneously take account of the transportation requirements and the use requirements, the extension rod inclined towards the back support plate is arranged, so that the first driving cylinder can be parallel to the back support plate as much as possible to meet the transportation requirement. With the design of the extension rod, the rotation connection point a of the piston rod is made closer to the back support plate than the rotation connection point b. Thus, the first driving cylinder is caused to obtain a certain inclination angle. During lifting of the back support plate, the driving rod of the first driving cylinder can push the back support plate to lift at a more convenient force application angle, so that the lifting requirement is satisfied.

However, if there is no extension rod, the driving rod needs to be rotatably connected to the linkage rod, and in order to obtain the inclination angle, only the cylinder block portion of the first driving cylinder can be uplifted in a direction away from the back support plate, and the overall volume of has to be increased, which makes it difficult to achieve the purpose of reducing the volume and the transportation cost.

In some embodiments, the back support plate is formed with a receiving groove, and the rotation connection point a is positioned in the receiving groove.

By adopting the above technical solution, the piston rod portion of the first driving cylinder extends into the receiving groove. Therefore, while the first driving cylinder is inclined, a part of the volume after the first driving cylinder is inclined extends into the receiving groove, and only a part of the piston rod is outside the back support plate, thereby further reducing the space between the first folding unit and the second folding unit during transportation, and reducing the vertical size during transportation.

In some embodiments, the cylinder block of the first driving cylinder is rotatably connected to the first base frame; the connection point of the piston rod and the back support plate is arranged at the position of the back support plate close to the lumbar support plate, and the connection point of the cylinder block and the first base frame is arranged at the position of the first base frame away from the lumbar support plate.

By adopting the above technical solution, when the back support plate is lifted, the piston rod of the first driving cylinder is close to the rotation point of the back support plate and the lumbar support plate. Thus, the first driving cylinder can achieve a desired lifting rotation effect without using a too long telescopic amount. The telescopic amount required by the first driving cylinder is reduced, so that the position of the first driving cylinder is more convenient, and the second folding unit is not touched during the transportation after folding because the first driving cylinder is too long.

In some embodiments, the first electric support plate and the second electric support plate are each formed with a receiving groove, the driving device includes a first driving cylinder, and when the first folding unit and the second folding unit are in a parallel state, a first part of the first driving cylinder is positioned in the receiving groove of the first electric support plate, a second part of the first driving cylinder is positioned in the receiving groove of the second electric support plate, a third part of the first driving cylinder is positioned at the gap between the first electric support plate and the second electric support plate.

By adopting the above technical solution, during transportation, the space between the first folding unit and the second folding unit can be effectively reduced, and the total vertical size during transportation can be reduced.

In some embodiments, the driving device includes a first driving cylinder for driving the movement of the first electric support plate and a second driving cylinder for driving the movement of the second electric support plate, the first driving cylinder and the second driving cylinder are both electric cylinders, and the motors of the two electric cylinders are oriented opposite to each other.

Since both the first electric support plate and the second electric support plate need to be driven, by adopting the above technical solution, it is possible to avoid overlapping of the positions of the first driving cylinder and the second driving cylinder after folding, and thus avoid increasing of the volume during transportation.

In some embodiments, the second electric support plate includes a hip support plate fixedly connected to the second base frame, a thigh support plate rotatably connected to the hip support plate, and a shank support plate rotatably connected to the thigh support plate; the driving device includes a second driving cylinder, and the cylinder block of the second driving cylinder is rotatably connected to the second base frame and the piston rod of the second driving cylinder is rotatably connected to the thigh support plate, and the rotation connection point is positioned between the thigh support plate and the shank support plate.

By adopting the above technical solution, the second driving cylinder jacks up the rotational position between the thigh support plate and the shank support plate, so that the thigh support plate and the shank support plate form a bent structure, and the knee position of the user can be naturally bent at the junction between the thigh support plate and the shank support plate, thereby improving the use experience.

Meanwhile, since only part of the thigh support plate and part of the shank support plate are lifted, the required lifting force does not need to be large, and the volume of the second driving cylinder does not need to be large. Therefore, the rotation connection point is positioned between the thigh support plate and the shank support plate, so that the required volume of the second driving cylinder is reduced and the occupied space is smaller.

In some embodiments, a second support rod is connected to each side of the second base frame where the shank support plate is located, one end of the second support rod is rotatably connected to the shank support plate, and the other end is rotatably connected to the second base frame.

By adopting the above technical solution, when the second electric support plate is lifted, the shank support plate may be limited by the second support rod, so that during the lifting process, the side of the shank support plate away from the second driving cylinder not only naturally hangs down under the action of gravity, but reaches a defined position, so that the shank can also be supported during use for more comfortable use.

In summary, the present application includes at least one of the following beneficial technical effects:

1. By folding the first folding unit and the second folding unit, the transportation cost of the bed frame is reduced.

2. With the design of the roller and the first support rod, the lifting of the back support plate is more quiet, and the power of the required first driving cylinder is reduced, so that the overall volume is reduced.

3. With the design of the receiving groove, the driving device is partially received in the receiving groove, thereby effectively reducing the space between the first folding unit and the second folding unit, and reducing the total vertical size during transportation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a first schematic structural diagram of an electric bed frame in use state according to the present application.

FIG. 2 is a second schematic structural diagram of an electric bed frame in use state according to the present application.

FIG. 3 is a schematic structural diagram of an electric bed frame in a folded state according to the present application.

FIG. 4 is an enlarged view of part A of FIG. 3.

FIG. 5 is a first schematic structural diagram of an electric bed frame in an extended state according to the present application.

FIG. 6 is an enlarged view of part B of FIG. 5.

FIG. 7 is a second schematic structural diagram of an electric bed frame in an extended state according to the present application.

DESCRIPTION OF THE EMBODIMENTS

The present application is further described in detail below with reference to FIGS. 1 to 7.

Embodiments of the present application disclose an electric bed frame.

Referring to FIGS. 1 and 2, an electric bed frame includes a frame body 1, an electric support plate 2 rotatably connected to the frame body 1, bed legs 3 detachably connected to the frame body 1, and a driving device 4 for driving the electric support plate 2 to rotate. In the use state, the bed legs 3 are connected to the frame body 1 through bolts, and are used to support the entire frame body 1. The driving device 4 drives the electric support plate 2 to rotate, uplift, or lower to restore the flattening, so as to satisfy the use requirements of the user for different bed frame inclination angles.

As shown in FIGS. 2 and 3, in the transportation state, the bed leg 3 is detached from the bed body for separate transportation, and the frame body 1 and the electric support plate 2 are transported after being folded, thereby reducing the total volume during transportation. Specifically, the frame body 1 includes a first base frame 11 and a second base frame 12 which are connected by a rotation mechanism 13, the first base frame 11 and the second base frame 12 are equal in size, and when the first base frame 11 and the second base frame 12 are rotated toward each other to extreme positions by the rotation mechanism 13, the first base frame 11 and the second base frame 12 are parallel.

As shown in FIGS. 2 and 4, the rotation mechanism 13 includes a first rotation plate 131 connected to the first base frame 11 and a second rotation plate 132 connected to the second base frame 12. The first rotation plate 131 and the second rotation plate 132 both extend obliquely towards the lower side of the frame body 1. A rotation hole is provided on a side away from the frame body 1. A rotation pin is rotatably connected in the rotation hole, and the first rotation plate 131 and the second rotation plate 132 are relatively rotated by the rotation pin. When the first base frame 11 and the second base frame 12 are folded, the two base frames are rotated toward to each other about the rotation pin, so that the edges of the two base frames can be avoided from colliding with each other during the rotation process, and the two base frames are parallel after rotation.

The electric support plate 2 includes a first electric support plate 21 connected to the first base frame 11, and a second electric support plate 22 connected to the second base frame 12. The first base frame 11 and the first electric support plate 21 form a first folding unit, and the second base frame 12 and the second electric support plate 22 form a second folding unit. When the first base frame 11 and the second base frame 12 rotate, the first electric support plate 21 rotates with the first base frame 11 and the second electric support plate 22 rotates with the second base frame 12, and finally the first folding unit and the second folding unit are parallel after rotation.

As shown in FIGS. 2 and 3, the driving device 4 is positioned below the first base frame 11 and the second base frame 12, and after the two base frames are rotated and retracted, the driving device 4 is received between the first base frame 11 and the second base frame 12. The driving device 4 includes a first driving cylinder 41 for driving the movement of the first electric support plate 21 and a second driving cylinder 42 for driving the movement of the second electric support plate 22. The first driving cylinder 41 and the second driving cylinder 42 are both electric cylinders. The motors of the two electric cylinders are oriented opposite to each other, so that the first driving cylinder 41 and the second driving cylinder 42 are staggered in position, the positions of the first driving cylinder 41 and the second driving cylinder 42 are prevented from being overlapped after the two base frames are folded, and the vertical size of the folded bed frame is prevented from being increased.

In order to reduce the volume occupied by the driving device 4 and reduce the vertical size during transportation after folding, the first electric support plate 21 and the second electric support plate 22 are each provided with a receiving groove 23 for receiving the driving cylinder. The receiving groove 23 is specifically divided into a cylinder receiving groove and a piston rod receiving groove, and may be a through groove or a blind groove for receiving different parts of the driving cylinder. For example, when the first folding unit and the second folding unit are in a parallel state, a first part of the first driving cylinder 41 is positioned in the receiving groove 23 of the first electric support plate 21, a second part of the first driving cylinder 41 is positioned in the receiving groove 23 of the second electric support plate 22, a third part of the first driving cylinder 41 is positioned at the gap between the first electric support plate 21 and the second electric support plate 22. Thus, the space between the first folding unit and the second folding unit occupied by the first driving cylinder 41 is reduced, and the reduction of the vertical size after folding is achieved.

As shown in FIGS. 2 and 5, the first electric support plate 21 includes a lumbar support plate 211 fixedly connected to the first base frame 11 and a back support plate 212 rotatably connected to one side of the lumbar support plate 211, and when in use, the back support plate 212 is driven to rotate by the first driving cylinder 41, so as to satisfy the user's use requirements. Specifically, the driving device 4 further includes a roller 43 abutting against the back support plate 212, a first support rod 44 having one end rotatably connected to the roller 43 and the other end rotatably connected to the first base frame 11. The first support rod 44 rotatably connected to the side surface of the first base frame 11, a set of first support rods 44 and a set of rollers 43 are arranged on each side of the first base frame 11. The two first support rods 44 are connected by a linkage rod 45 at the end of each support rods away from the roller 43, a piston rod of the first driving cylinder 41 is connected to the linkage rod 45 by an extension rod 46, and a cylinder block of the first driving cylinder 41 is rotatably connected to the first base frame 11, so that a force can be applied to the two first support rods 44.

When the back support plate 212 needs to be uplifted, the piston rod of the first driving cylinder 41 sequentially drives the extension rod 46, the linkage rod 45, the first support rod 44 and the roller 43 to move, so that the back support plate 212 is uplifted via the abutting relationship between the roller 43 and the back support plate 212, and during the uplifting process, the wear between the roller 43 and the back support plate 212 is reduced due to the rolling of the roller 43, and the purpose of noise reduction is also achieved. In order to further reduce noise and wear, a backing plate 213 is fixedly connected to the back support plate 212 at the butting position of the roller 43.

The purpose of driving the back support plate 212 in this manner is to reduce the volume of the transportation state after overlapping. The first driving cylinder 41 needs to be designed as small as possible. Hence, the power is reduced. After the roller 43 is used, the frictional resistance during lifting can be greatly reduced. Even if the power of the first driving cylinder 41 is reduced, the requirements of the use process can be satisfied. Thus, the transportation requirements and the use requirements are both satisfied.

When the first driving cylinder 41 is installed, since the first driving cylinder 41 needs to jack up the back support plate 212, the length of the first driving cylinder 41 itself is very long. If the inclination angle between the first driving cylinder 41 and the back support plate 212 tends to be more vertical, due to the limitation caused by the length of the first driving cylinder 41 itself, the more space is occupied, the larger the vertical size of the first driving cylinder 41 is during transportation, and the higher the transportation cost is. Therefore, from the perspective of transportation requirements, the first driving cylinder 41 and the back support plate 212 are expected to be more parallel. However, in consideration of the use requirements of the user, the more the inclination angle of the first driving cylinder 41 and the back support plate 212 tends to be vertical, the smaller the moment arm is in lifting, and the more the back support plate 212 can be stably lifted.

As shown in FIGS. 5 and 6, in order to simultaneously take account of the transportation requirements and the use requirements, the first driving cylinder 41 needs to be arranged as horizontally as possible, and the piston rod and the back support plate 212 need to have a certain included angle, so that the extension rod 46 inclined towards the back support plate 212 is arranged. The first driving cylinder 41 has two connecting points, namely, a rotation connecting point a of the piston rod and the extension rod 46, and a rotation connecting point b of the cylinder block and the first base frame 11. The extension rod 46 is inclined towards the back support plate 212. Hence, the distance between the rotation connection point a and the back support plate 212 is smaller than the distance between the rotation connection point b and the back support plate 212. Thus, the first driving cylinder 41 tends to be integrally parallel to the back support plate 212 before raising the back support plate 212, and has an angle inclined towards the back support plate 212. During lifting of the back support plate 212, the driving rod of the first driving cylinder 41 can push the back support plate 212 to lift at a more convenient force application angle, so that the lifting requirement is satisfied.

However, if there is no extension rod 46, the driving rod needs to be rotatably connected to the linkage rod 45, and in order to obtain the inclination angle, only the cylinder block portion of the first driving cylinder 41 can be uplifted in a direction away from the back support plate 212, and the volume of the folded bed frame has to be increased, which makes it difficult to achieve the purpose of reducing the volume and the transportation cost. In order to further compress the volume of the folded bed frame, the receiving groove 23 is provided on the back support plate 212, and the rotation connection point a is positioned in the receiving groove 23.

In order to reduce the telescopic amount required by the first driving cylinder 41, the connecting point of the piston rod and the back support plate 212 is arranged at the position of the back support plate 212 close to the lumbar support plate 211. The connection point of the cylinder block and the first base frame 11 is arranged at the position of the first base frame 11 away from the lumbar support plate 211. Thus, the first driving cylinder 41 can achieve a desired lifting rotation effect without using a too long telescopic amount. The telescopic amount required by the first driving cylinder 41 is reduced, so that the position of the first driving cylinder 41 is more convenient, and the second folding unit is not touched during the transportation after folding because the first driving cylinder 41 is too long.

As shown in FIGS. 2 and 7, the second electric support plate 22 includes a hip support plate 221 fixedly connected to the second base frame 12, a thigh support plate 222 rotatably connected to the hip support plate 221, and a shank support plate 223 rotatably connected to the thigh support plate 222. The cylinder block of the second driving cylinder 42 is rotatably connected to the second base frame 12, the piston rod of the second driving cylinder 42 is rotatably connected to the thigh support plate 222, and the rotation connection point is positioned between the thigh support plate 222 and the shank support plate 223. When the second driving cylinder 42 is not in operation, the thigh support plate 222 and the shank support plate 223 are laid on the surface of the second base frame 12. During driving, the second driving cylinder 42 jacks up the rotational position between the thigh support plate 222 and the shank support plate 223, so that the thigh support plate 222 and the shank support plate 223 form a bent structure, and the knee position of the user can be naturally bent at the junction between the thigh support plate 222 and the shank support plate 223, thereby improving the comfort of use.

Meanwhile, since only part of the thigh support plate 222 and part of the shank support plate 223 are lifted, the required lifting force does not need to be large, and the volume of the second driving cylinder 42 does not need to be large. Therefore, the piston rod of the second driving cylinder 42 is connected between the thigh support plate 222 and the shank support plate 223, so that the required volume of the second driving cylinder 42 is reduced and the occupied space is smaller.

A second support rod 47 is disposed on each side of the second base frame 12, one end of the second support rod 47 is rotatably connected to the shank support plate 223 at a position away from the thigh support plate 222, and the other end is rotatably connected to the second base frame 12. When the second electric support plate 22 is lifted, the shank support plate 223 is limited by the second support rod 47. During the lifting process, the side of the shank support plate 223 away from the second driving cylinder 42 not only naturally hangs down under the action of gravity. Instead, one end is pulled by the thigh support plate 222 and the other end is limited by the second support rod 47, therefore the end away from the thigh support plate 222 cannot hangs down completely. Instead, a certain angle of lifting is obtained, and the shank of the user can also be supported for more comfortable use.

The implementation principle of the electric bed frame according to an embodiment of the present application is as follows: when the electric bed frame needs to be transported, the first folding unit and the second folding unit are folded by the rotation mechanism 13. In this case, the driving device 4 is partially received in the receiving groove 23, and part of the driving device 4 is positioned between the first folding unit and the second folding unit, and therefore, the volume formed by the whole bed frame is reduced, and the required freight is also reduced, and the purpose of reducing the shipping cost is achieved.

The above description is only preferred embodiments of the present application and is not intended to limit the protection scope of the present application. Therefore, all equivalent changes of the structure, shape or principle according to the spirit of the present application should be all included in the protection scope of the present application. 

What is claimed is:
 1. An electric bed frame, comprising a frame body, an electric support plate rotatably connected to the frame body, a driving device connected to the frame body and driving the electric support plate to rotate, and bed legs detachably connected to the frame body, wherein, the frame body comprises a first base frame and a second base frame, the electric support plate comprises a first electric support plate connected to the first base frame, and a second electric support plate connected to the second base frame, the first base frame and the first electric support plate form a first folding unit, and the second base frame and the second electric support plate form a second folding unit; the first folding unit and the second folding unit are rotatably connected by a rotation mechanism, and when the first folding unit and the second folding unit are rotated to an extreme position, the first folding unit and the second folding unit are parallel, and the driving device is positioned between the first folding unit and the second folding unit; the first electric support plate comprises a lumbar support plate fixedly connected to the first base frame and a back support plate rotatably connected to one side of the lumbar support plate, the driving device comprises a roller abutting against the back support plate, a first support rod having one end rotatably connected to the roller and the other end rotatably connected to the first base frame, and a first driving cylinder connected to the first base frame and driving the first support rod to push the back support plate close to or away from the first base frame.
 2. The electric bed frame according to claim 1, wherein the roller and the first support rod are provided on each side of the back support plate, and the two first support rods are connected by a linkage rod at one end of each first support rods away from the roller; a cylinder block of the first driving cylinder is rotatably connected to the first base frame, and a piston rod of the first driving cylinder is rotatably connected to the linkage rod.
 3. The electric bed frame according to claim 2, wherein the piston rod of the first driving cylinder is connected to the linkage rod by an extension rod, one end of the extension rod is fixedly connected to the linkage rod, the other end of the extension rod is inclined towards the back support plate and is rotatably connected to the piston rod to form a rotation connection point a, and the cylinder block of the first driving cylinder is rotatably connected to the first base frame and forms a rotation connection point b; a distance between the rotation connection point a and the back support plate is smaller than a distance between the rotation connection point b and the back support plate.
 4. The electric bed frame according to claim 3, wherein the back support plate is formed with a receiving groove, and the rotation connection point a is positioned in the receiving groove.
 5. The electric bed frame according to claim 1, wherein the cylinder block of the first driving cylinder is rotatably connected to the first base frame; the connection point of the piston rod and the back support plate is arranged at the position of the back support plate close to the lumbar support plate, and the connection point of the cylinder block and the first base frame is arranged at the position of the first base frame away from the lumbar support plate.
 6. The electric bed frame according to claim 1, wherein the first electric support plate and the second electric support plate are each formed with a receiving groove, the driving device comprises a first driving cylinder, and when the first folding unit and the second folding unit are in a parallel state, a first part of the first driving cylinder is positioned in the receiving groove of the first electric support plate, a second part of the first driving cylinder is positioned in the receiving groove of the second electric support plate, a third part of the first driving cylinder is positioned at the gap between the first electric support plate and the second electric support plate.
 7. The electric bed frame according to claim 1, wherein the driving device comprises a first driving cylinder for driving the movement of the first electric support plate and a second driving cylinder for driving the movement of the second electric support plate, the first driving cylinder and the second driving cylinder are both electric cylinders, and motors of the two electric cylinders are oriented opposite to each other.
 8. The electric bed frame according to claim 1, wherein the second electric support plate comprises a hip support plate fixedly connected to the second base frame, a thigh support plate rotatably connected to the hip support plate, and a shank support plate rotatably connected to the thigh support plate; the driving device comprises a second driving cylinder, and the cylinder block of the second driving cylinder is rotatably connected to the second base frame and the piston rod of the second driving cylinder is rotatably connected to the thigh support plate, and the rotation connection point is positioned between the thigh support plate and the shank support plate.
 9. The electric bed frame according to claim 1, wherein a second support rod is connected to each side of the second base frame where the shank support plate is located, one end of the second support rod is rotatably connected to the shank support plate, and the other end is rotatably connected to the second base frame. 